Bench marks were historically used to record the height above sea level of a location as surveyed against the Mean Sea Level data (taken at Clarendon Dock, Belfast, for Northern Ireland data, Newlyn in Cornwall for data in Great Britain and Portmoor Pier, Malin Head, for data relating to the Republic of Ireland). They were used as part of a greater surveying network by the UK Ordnance Survey, Ordnance Survey Northern Ireland (OSNI) and the Ordnance Survey Ireland (OSI). If the exact height of one bench mark is known then the exact height of the next can be found by measuring the difference in heights, through a process of spirit levelling. In this way hundreds of thousands of bench marks were sited all around the UK & Ireland from the mid 19th to late 20th centuries. There are several distinct types of bench mark:

Bench marks are commonly found on older buildings or other semi-permanent features such as stone bridges or walls. Due to updated mapping techniques and technological advances such as GPS, bench marks are no longer maintained. Many are still in existence and the markers will probably remain until they are eventually destroyed by redevelopment or erosion.

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Discussion on J3372

”In 1976 Queen’s unveiled a new piece of kinetic sculpture built by staff and students from the School of Mechanical Engineering and located near the Botanic Avenue entrance to Belfast’s Botanic Gardens. It became a well-loved landmark even after its moving parts had seized and rusted and great sadness marked its eventual removal in 2005 to make way for the Sir Anthony Reilly Library.

Industry, as the piece was known, was the largest work and only piece of public sculpture by its designer, Barry Orr (1930-2000). Born in Eglantine Avenue, Belfast, he attended Methodist College and worked in the textile industry and as an entertainment booker for the Talk of the Town nightclub in Belfast. He eventually became Press Officer for UTV and then Enterprise Ulster. Although his work is included in many public and private collections, Orr never considered himself to be an artist, describing his kinetic pieces as ?mechanical doodles?. He was inspired to make the first of these when he discovered that his teething child was soothed by the sound of dried peas in a tin and rather than continue to shake it manually, he built a machine to do it for him.

Orbs work is part of the art historical tradition of improbable machines and has an obvious affinity with the famous drawings of William Heath Robinson (1872 ?1944) the English illustrator, whose name has entered the language as a description of any unnecessarily complex and implausible contraption. Heath Robinsons machines existed on paper and functioned only in the imagination. A more direct influence and a personal hero, was Frederick Roland Emett (1906-1990), another English cartoonist and constructor of whimsical kinetic sculpture, amongst whose most famous works were Nellie, the steam locomotive constructed for the 1951 Festival of Britain and one of its most popular attractions, and Professor Potts? elaborate time-saving domestic devices for the 1968 film Chitty Chitty Bang Bang.

When it was dismantled, Industry was discovered to be beyond repair, and after discussion with Barry Orbs family it was decided not to remake the work but to hold an exhibition celebrating the artist’s work and to commission a new site specific work in the spirit of recycling and re-imagination.”